How do you get the best deal on a Windows 8 Pro upgrade?

You can get a smoking deal on an upgrade to Windows 8 Pro if you're ready to make that purchase before January 31, 2013. But there are some gotchas, and one inexplicable and unfair pricing decision means that early buyers of Windows 8 PCs pay more than Windows 7 users.

(d) Any of the above, depending on which version of Windows you're running today.

Microsoft has simplified the upgrade process for Windows 8 dramatically, at least for early adopters, starting with its decision to sell only two retail editions.

Between now and February 1, 2013, Microsoft is offering upgrades to Windows 8 Pro, the full-featured edition whose Windows 7 equivalent typically costs $200. (Upgrades to the less expensive base version of Windows 8 are not available at all right now, and won’t be available until these initial promotional offers are over.)

That makes for some smoking deals. But there are still a few gotchas to be had in the process. And one inexplicable pricing decision actually penalizes customers who are among the first to purchase PCs preloaded with Windows 8.

Here are the details.

If you are currently using Windows 7, Windows Vista, or Windows XP, you qualify for a $40 upgrade to Windows 8 Pro.

Start here to launch the Windows Upgrade Assistant, and you will rapidly get to this screen:

Click Order, follow the prompts, enter your payment details (PayPal or credit card), and $40 later you will have a product key and an opportunity to download the Windows 8 software. You can install the upgrade immediately or save it for later.

It’s a great deal. And note that you do not have to use your discounted upgrade on the machine where you downloaded the code. You are free to snag the product key and the installer files and use them on a different qualifying PC later.

But you can do better than that $40 price.

If you purchase a PC running Windows 7 Home Basic, Home Premium, Professional, or Ultimate between June 2, 2012, and January 31, 2013, you qualify for a heavily discounted $15 upgrade to Windows 8 Pro. You have to register at this website, and await a promo code that will arrive via email from Microsoft.

After you receive the promo code via email, follow the instructions to run the Upgrade Assistant. When you get to the purchase page, you’ll have an opportunity to enter that code and knock $25 off the total price. The payment screen should look like this:

So far, so good.

But what if you waited and purchased a new PC with Windows 8 already installed? Surely Microsoft will reward you as an early adopter, right?

Not so fast.

Most PCs sold at retail, as far as I have been able to determine, come with the base edition of Windows 8. All 15 notebooks sold at the Microsoft Store, for example, have this edition installed, with no upgrade option.

If you buy one of those PCs and bring it home, what happens if you run the Windows Upgrade Assistant to snag a $40 upgrade? You get a misleading error message telling you that the option you selected isn’t available for your country.

What you have to do instead is go to System Properties and click Get more features with a new edition of Windows.

That takes you here, where you (quite logically) say you want to purchase a new product key online:

And when you do, you end up at this screen:

Yes, that’s right. As one of the first people to support the new Windows 8 hardware, your reward is an upgrade that costs $30 more than the price that laggards paid.

Does that seem fair? No, not really.

Interestingly, if you snag a $40 Windows 8 Pro upgrade key from a Windows 7 (or earlier) PC, that key will work to upgrade your Windows 8 PC. Just use the I already have a product key option and enter that upgrade key. I can confirm it works just fine.

Even better is to pay for your upgrade at the same time you order a new PC. That won’t work with boxed PCs sold at retail outlets like Best Buy and Walmart, but it is always an option with built-to-order machines from Dell, HP, and other online suppliers. I’ve seen Windows 8 Pro upgrades from Dell quoted at $35 when ordered with a new PC. If it’s not an option on the web ordering screen, try picking up the phone and talking to a live agent. They’re often willing to deal on options like this.

Meanwhile, I’m testing all the upgrade and clean install possibilities I can to see what works and what doesn’t work. I’ll have those results in a follow-up post. If you have specific scenarios you want me to look at, send me a note via the contact link in my bio. (Don’t leave them in the Talkback section—they’re likely to get lost in the noise there.)

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